Field of the Invention
The illegal use of certain veterinary drugs has resulted in the development of a flourishing illicit market in these drugs which in turn presents a potential hazard for the consumer of product from treated animals.
Steers are traditionally used in the beef industry rather than bulls. Steers are less efficient, they grow 10% slower and have more fat and poorer conformation than bulls. Thus, beef producers used anabolic agents to increase growth before they were banned. However, since the EC ban in 1987, there have been varying allegations of illegal use of prohibited production enhancers in beef cattle. The possibility that a significant portion of beef might have residues of illegal growth enhancers could threaten consumption of beef.
Mandatory testing by national authorities of fresh meat, in compliance with EC Directives, covers a range of veterinary medicines and banned substances.
The extent of monitoring in compliance with EC Directives and `on suspicion` is limited by the resources available to the authorities and thus will inevitably result in only a limited number of samples being monitored. In addition to this, the analytical methods used are laborious and costly. A further disadvantage of currently available commercial immunological assays is that they require at least one day for an end-point determination to be made. Thus the carcase being tested would have left the abattoir before the assay result is available.
An enzyme immunoassay screening for synthetic anabolic estrogens and androgens is known from Degand et al (Journal of Chromotography, 489 (1989) p235-234). The assay is an enzyme immunoassay involving either horseraddish peroxidase or Beta-lactamase, which is conducted on bovine urine to detect diethylstilbestrol, nortestosterone, methyltestosterone and trenbolane. High-performance liquid chromatography following immunoaffinity pre-treatment to determine nortestosterone levels in biological samples is known from Haasnoot (Journal of Chromotography, 489 (1989) p157-171).
The analytical test protocol of the present invention represents a new approach to surveillance of fresh meat for drug residues. The approach has been to apply rapid clinical diagnostic techniques to veterinary drug residue analysis. This has the potential to permit large numbers of samples to be processed rapidly and much more cheaply than is currently the case. This approach permits the monitoring of large numbers of animals as they pass through abattoirs and offers the possibility of "Carcase Quality Certification (CQC)" before the carcase is allowed to enter the food chain.
The invention provides a series of semi-automated tests for a range of veterinary drugs, such as `Angel Dust` (the Beta-Agonists-Clenbuterol, Salbutamol, Terbutaline etc), and for illegal hormonal growth promoters (Zeranol, Trenbolone, Stilbenes etc).